Add some inline docs to `media-views.js` and remove some unnecessary comments...

Add some inline docs to `media-views.js` and remove some unnecessary comments from a few `super` calls.

Props gcorne.
See #26870.


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git-svn-id: https://core.svn.wordpress.org/trunk@26993 1a063a9b-81f0-0310-95a4-ce76da25c4cd